212 THE STORY OF THB EALTH AND MAN. 



and whales and their allies, but there were vast num- 

 bers of marine reptiles, and many of these of gigantic 

 size. Britain at present does not possess one large 

 reptile, and no marine reptile whatever. In the 

 Mesozoic, in addition to the great Dinosaurs and 

 Pterodactyls of the land- it had at least fifty or sixty 

 species of aquatic reptiles, besides many turtles. Some 

 of these were comparable in size with our modern 

 whales, and armed with tremendous powers of destruc- 

 tion. America is not relatively rich in remains of 

 Mesozoic Saurians, yet while the existing fauna of the 

 temperate parts of North America is nearly destitute 

 of aquatic reptiles, with the exception of the turtles, 

 it can boast, according to Cope's lists, about fifty 

 Mesozoic species, many of them of gigantic size, and 

 the number of known species is increasing every year. 

 When it is taken in connection with these statistics, 

 that while we know all the modern species, we know 

 but a small percentage of the fossils, the discrepancy 

 becomes still more startling. Further, from the num- 

 ber of specimens and fragments found, it is obvious 

 that these great aquatic saurians were by no means 

 rare ; and that some of the species at least must have 

 been very abundant. Could we have taken our post 

 on the Mesozoic shore, or sailed over its waters, we 

 should have found ourselves in the midst of swarms of 

 these strange, often hideous, and always grotesque 

 creatures. 



Let us consider for a little some of the more con- 

 spicuous forms, referring to our illustration for their 



